CSDC 500

A war of aggression is intrinsically immoral. In the tragic case where such a war breaks out, leaders of the State that has been attacked have the right and the duty to organize a defence even using the force of arms.¹⁰⁴⁹ Cf. Catechism of the Catholic Church, 2265. To be licit, the use of force must correspond to certain strict conditions: “the damage inflicted by the aggressor on the nation or community of nations must be lasting, grave and certain; all other means of putting an end to it must have been shown to be impractical or ineffective; there must be serious prospects of success; the use of arms must not produce evils and disorders graver than the evil to be eliminated. The power of modern means of destruction weighs very heavily in evaluating this condition. These are the traditional elements enumerated in what is called the ‘just war' doctrine. The evaluation of these conditions for moral legitimacy belongs to the prudential judgment of those who have responsibility for the common good”.[1050 ] If this responsibility justifies the possession of sufficient means to exercise this right to defence, States still have the obligation to do everything possible “to ensure that the conditions of peace exist, not only within their own territory but throughout the world”.¹⁰⁵¹ Pontifical Council for Justice and Peace, The International Arms Trade. An ethical reflection (1 May 1994), ch. 1, 6: Libreria Editrice Vaticana, Vatican City 1994, p. 13. It is important to remember that “it is one thing to wage a war of self-defence; it is quite another to seek to impose domination on another nation. The possession of war potential does not justify the use of force for political or military objectives. Nor does the mere fact that war has unfortunately broken out mean that all is fair between the warring parties”.¹⁰⁵² Second Vatican Ecumenical Council, Pastoral Constitution Gaudium et Spes, 79: AAS 58AAS — Acta Apostolicae Sedis (official gazette of the Holy See)Volume 58 (1966) at vatican.va — scanned PDF (1966), 1103.